Model aeroplane



April 6, 1948. E. MIOSTHOF 1 v 2,439,054

MODEL AEROlfLANE Filed March 27, 1946 2 Sheets-Sheet 1 dcq'z'n D2 oat/2 of Inventor bgigiiabbornes i I April 6, 1948. E. MOSTHOF MODEL AEROPLANE Filed March 27, 1946 v 54mm nzwsizof' Unvenbor 5 (lttorneg Patented Apr. 6, 1948 MQ lZELAEROPLANE nid yindnosthof, Orange, d-

.27, %B.- S.et.i.a .iN 6514.45

(Chili-4718:)

G-Claims.

1 The presentinvention deals with a motor operated model aeroplane. More specifically, it relates'to an electrically driven model plane, the

speed of which is aontnollednby a device held in I the hand of the operator.

*Imtihepast, toy planesrlmm been equipped with small gasoline driven engines. fThese-ane of the constant speed type-the only contaol being on the elevators of the plane operated by wires held in thethand of the operator. -fiuchcontrol-merely affects altitude, the engine speed -remaini-n the same. Usually -these =planes are run until they are out of fuel, whereupon they fall to the ground and often crash with demolition of both plane and motor.

An object of my invention is to provide a small electrical motor to drive the plane. Another object is to provide a means for controlling the speed of said motor by using conventional control wires which are simultaneously employed for operating the elevators. Another object is to enable the safe landing of the plane, so as to preserve intact the plane and its contents. Other objects will become apparent from the following description.

The invention may be more clearly understood by reference to the drawings in which Figure 1 is a side view of the plane and the controlling wires. Figure 2 is a side view, partly in crosssection, of the controller hand-grip, while Figure 3 is a top view thereof. Similar numbers refer to similar parts in the different figures.

Referring again to the drawings, numeral l represents a model aeroplane, the wing of which is omitted to more clearly show the assembly employed in the present invention. The plane has elevators 2 and propeller 3. Mounted in the front of the plane is miniature electric motor 4, preferably of the high speed type developed during the recent war, running at, say, 30,000 R. P. M. Directly connected to the motor is gear speed reducer 4 which reduces the speed to say, 7500-10,000 R. P. M. at the propeller shaft to which it is directly connected. This speed reduction not only gives the propellers a reasonable and safe airfoil velocity of flow, but also provides more power to the propeller shaft.

The elevators 2 have arms 5 to which are attached guide Phosphor bronze enamel-covered wires 6 and 1. These are run through curved guides 8 and 9 which are mounted permanently and in a fixed position in the plane, allowing the guide wires to project through opening H1 at the side of the plane. These wires, which are usually 35-50 ft. long, are led to controller hand-grip H,

2 the wires-being firm-1y attached-to the top and bottom of saidgrip, respectively. Towires 6 and I and ip the vicinity of "the controller hand-grip 4-1 a-re--attachedwire l-z-and l3 leading to term-inals of battery4-4.

The grip portion I 5 of controller hand-grip -'i l is drilled toprovide' hole "it in the top part; terminati-ngin --wider*hole H at the-bottom. lnhole t is coiled resistancewi-re l-8,-held in place by set screw &1, terminatingbinding post-20. the upper narrower he'le 1 5 is inserted rod '21, having sliding contact 22 on thebottom,sliding along resistance coil i8, and terminating in head 23 which is made to project above the top of grip 1-5 by spring 24. By pressing head 23, slide 22 cuts out more resistance in rheostat 18, thereby passing more current from battery i4 through wires 6 and I, thus speeding up electric motor 4. A stop can be attached to the top of rod 2| to enable one to quickly find the correct resistance setting for optimum cruising speed.

In the upper portion of grip I5 is drilled hole 26 carrying wire 25 which is connected to bus bar 21. Sliding contact 28 rubs against rod 2!. Wire 26 issues through hole 29 to the side of grip l5 and into one of the contacts of shut-cit switch 30. From binding post 20, a wire 3| is run into hole 32 at the bottom of grip l5, terminating at fuse 33 which can be removed by removing plate 34. The fuse is inserted to prevent fusion of wires in the circuit in the event a short occurs. The other end 35 of fuse 33 is connected to the other terminal of shut-off switch 30.

Bus bar 21 on the upper surface of grip I5 is held in place by bolt 36 which also acts as a binding post for wire 1. Likewise at the bottom of grip l5, bus bar 31 is held in place by bolt 38 which also acts as a binding post for wire 6. Wires 39 and 40 are tapped into 6 and l and led into contact unit 4| capable of being plugged into a cigar lighter attachment of an automobile, which would supply the necessary power. I

In the operation of the invention, plane I is laid on a level spot and wires 6 and I stretched out evenly and grip control H is held firmly in the hand. Then switch 30 is flicked to the on position and head 23 of rod 2| is gradually depressed, causing the ropeller 3 to speed up. By turning grip II, it is possible to put more tension on either wire 6 or 1, thus either raising or lowering the elevators and allowing the plane to take 01f. In taking off, head 23 is depressed as far as it will go to give motor 4 full power. When the required elevation is reached,

head 23 may be allowed to come up to cruising speed.

When it is desired to land the plane, pressure is gradually removed from head 23 and at the same time, wires 6 and I are manipulated so that the elevators allow the plane to drop to lower altitude. The plane is allowed to circle in this manner until the ground is reached.

Grip 15 is preferably made of insulating material such as Wood, plastic; fiber, or the like.

It will be observed that conducting guide wires 6 and I are connected to motor 4 by conducting wires 42 and 43 which transmit electric current from the guide wires to the electric motor.

I claim:

1. A model plane adapted to fly, having a small electric motor mounted therein and connected to the propeller, two electrically conducting wires, insulated from each other, leading into the plane, electrical connecting means between said wires and said motor to allow operation of the motor by means of current passing through said wires, two cables, each attached in controlling relation to the elevators of the plane on one end and to each of the wires leading into the plane on the other, in such manner as to allow moving of the elevators by moving of said wires to efiect any desired change of altitude of the plane while the motor is operating, a hand grip connected to the terminals of the wires outside of the plane, and a. source of electric power to be fed to said wires.

2. A model plane according to claim 1 in which the hand grip is provided with control means to vary the speed of the motor.

3. A model plane according to claim 2 in which the motor is provided with a speed reducer to which the propeller is attached.

4. A model plane according to claim 1 in which the source of electric power is a plug fitting into a cigar lighter in an automobile.

5.A model plane according "to claim 1 in which the hand grip is-provided with a variable rheostat connected to the guide wires, said rheostat having a movable contact, a rod attached to saidcontact and projecting out of the top of REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 7 Date 1,769,414 Brandon et al July 1, 1930 2,292,416

Walker Aug. 11, 1942 

